In June 2012 the World Health Organization classified diesel exhaust fumes as a known carcinogen.1 Exhaust fumes from petrol vehicles remained in the ‘possibly carcinogenic’ category. The key studies that lead to the change of classification for diesel concerned occupational exposure for miners, with one study showing a trebling in risk for the highest quartile of exposure compared with the lowest.2

An editorial on the miners study called for, “stringent occupational and […] environmental standards for diesel exhaust emissions”.3 New standards could be particularly beneficial for staff working at drive-through windows, usually in fast food restaurants. Drive-through staff spend many hours at an open window close to vehicles with idling engines. Drive-through areas are often poorly ventilated because of their enclosed shape. This combination of idling engines and poor ventilation may mean that staff at drive-through windows are exposed to potentially dangerous levels of exhaust fumes.

A study of exposure to carbon monoxide in drive-through clinics operating for two hours found an increased exposure due to poorly maintained vehicles.4 However, this study did not examine particulate matter, which is the probable cause of lung cancer from diesel exhaust exposure.1

Cancer is not the only health concern from exposure to exhaust fumes. Exposure can also exacerbate asthma and lead to hospitalisation for respiratory disease. Long-term exposure to traffic pollution has been shown to impair lung growth in children aged 10 to 18,5 an age range which covers many drive-through staff. Exposure to traffic pollution is particularly dangerous during pregnancy and may cause preterm birth or low birth weight.6

Given the potentially high exposure to staff working at drive-through windows, senior management of fast food restaurants should consider the following:

1Conduct studies to determine the levels of exposure to exhaust fumes for staff at drive-through windows.

2Encourage stationary drivers to turn off their engines while they wait to reduce the levels of exhaust fumes.

3Prevent pregnant staff from working at drive-through windows in order to minimise exposure for this vulnerable group.

4Explore changes to the physical structure of drive-through areas to increase ventilation in order to better dissipate the fumes.

There is no specific study of the health effects of traffic pollution in fast food workers at drive-through windows. However, there is good evidence that those people who live near major roads suffer the greatest health effects from exhaust fumes, and that children are particularly vulnerable to the effects of traffic pollution. Drive-through areas have the potential to create prolonged exposure to high levels of exhaust fumes, due to the combination of idling engines and poor ventilation. There are many viable options for reducing exposure which could lead to great health benefits for the often young staff who work at the windows.